Integrated Circuit Devices and Methods and Apparatuses for Designing Integrated Circuit Devices

1. A non-transitory machine readable medium containing executable computer program instructions which when executed by a data processing system cause the data processing system to perform a method of designing an integrated circuit (IC), the method comprising: searching, within a representation of the IC, a shielding mesh of the IC representation for at least one first signal line determining that the at least first signal line routed through the shielding mesh comprising a first set of reference voltage lines and a second set of reference voltage lines does not require shielding; determining that at least one second signal line should be shielded; moving the at least one first signal line to a location outside the shielding mesh if the at least one first signal line does not require shielding; and placing the at least one second signal line into the shielding mesh of the IC representation.

2. A non-transitory machine readable medium as in claim 1 wherein the searching comprises searching for neighboring signal lines which have non-overlapping signal transition times.

3. A non-transitory machine readable medium as in claim 2 wherein the non-overlapping signal transition times are separated by at least a predetermined period of time.

4. A non-transitory machine readable medium as in claim 1 wherein the at least one first signal line is removed to a layer which does not contain the shielding mesh or another shielding mesh.

5. A non-transitory machine readable medium as in claim 1 wherein the at least one first signal line is removed from the shielding mesh which is in at least a first layer and is placed in a region of the first layer which does not include another shielding mesh.

6. A non-transitory machine readable medium as in claim 1 , further comprising determining a need to speed up a third signal line in the shielding mesh; and deleting a shield wire in the shielding mesh that separates the third signal line from a fourth signal line.

7. An integrated circuit comprising: a memory; and a processor coupled to the memory, wherein the processor is configured to search, within a representation of the IC, a shielding mesh of the IC representation for at least one first signal line, wherein the processor is configured to determine that the at least first signal line routed through the shielding mesh comprising a first set of reference voltage lines and a second set of reference voltage lines does not require shielding, wherein the processor is configured to determine that at least one second signal line should be shielded, wherein the processor is configured to move the at least one first signal line to a location outside the shielding mesh if the at least one first signal line does not require shielding; and wherein the processor is configured to place the at least one second signal line into the shielding mesh of the IC representation.

8. The integrated circuit of claim 7 wherein the searching comprises searching for neighboring signal lines which have non-overlapping signal transition times.

9. The integrated circuit of claim 8 wherein the non-overlapping signal transition times are separated by at least a predetermined period of time.

10. The integrated circuit of claim 7 wherein the at least one first signal line is removed to a layer which does not contain the shielding mesh or another shielding mesh.

11. The integrated circuit of claim 7 wherein the at least one first signal line is removed from the shielding mesh which is in at least a first layer and is placed in a region of the first layer which does not include another shielding mesh.

12. The integrated circuit of claim 7 , wherein the processor is further configured to determine a need to speed up a third signal line in the shielding mesh; and and wherein the processor is further configured to delete a shield wire in the shielding mesh that separates the third signal line from a fourth signal line.

13. A method to design an integrated circuit (IC) comprising: searching within a representation of the IC, a shielding mesh of the IC representation for at least one first signal line, determining that the at least first signal line routed through the shielding mesh comprising a first set of reference voltage lines and a second set of reference voltage lines does not require shielding; determining that at least one second signal line should be shielded; moving the at least one first signal line to a location outside the shielding mesh if the at least one first signal line does not require shielding; and placing the at least one second signal line into the shielding mesh of the IC Representation, wherein at least one of the searching, determining, moving, and placing is performed by a processor.

14. The method of claim 13 wherein the searching comprises searching for neighboring signal lines which have non-overlapping signal transition times.

15. The method of claim 14 wherein the non-overlapping signal transition times are separated by at least a predetermined period of time.

16. The method of claim 13 wherein the at least one first signal line is removed to a layer which does not contain the shielding mesh or another shielding mesh.

17. The method of claim 13 wherein the at least one first signal line is removed from the shielding mesh which is in at least a first layer and is placed in a region of the first layer which does not include another shielding mesh.

18. The method of claim 13 , further comprising determining a need to speed up a third signal line in the shielding mesh; and deleting a shield wire in the shielding mesh that separates the third signal line from a fourth signal line.